Artificial tooth



QCLB, 1931.- v B. LIBROOKIS 1,826,271

ARTIFICIAL TOOTH Filed July 8, 1926 745' the pin and thereby to thedental bridge the taching device mounted thereon of a slightly 90provide an interchangeable or replacement ment on the tooth and rootfacing. 95

Fatented Oct. 6,1931 i I nniTso sTATss PATENT OFFICE BENJAMIN L. BROOKS,0F LYNGHBURG, VIRGINIA ARTIFICIAL roorn Application filed July 8, 1926.Serial No. 121,208.

This invention relates to removable intergether with the manner andposition of the changeable porcelain facings having porcepin attachingdevice which has been made a lain root extensions with the root endporpart of the metal backing of the bridge,whic tions somewhat rounded.backing serves as the abutment span or sup- The root end surface isordinarily glazed port. and adapted for dummies and pontics of The slotin the porcelain faced tooth enters dental bridgework. The glazed endportion from the lingual side. The pin from the atis intended to fit upflush to the tissue ofthe taching device projects from the metalbackalevolar ridge or somewhat into the root socking toward the labialor buccal surface in et alevolar ridge thereby forming and prosuch amanner as to allow the porcelain facing ducing a more natural andsanitary arrangerootto slip back on the pin toward the lingual Inentwhich approaches closely to the anaat about right angles to the longaxis of the tomieal tooth form at the point of the gum tooth facing, orslanting upwardly and back line and the alevolar ridge. ward.

An object of this invention is, to provide a A further object of thisinvention is to slot or recess extending into the lingual surprovide atwo surface reciprocal anchorage face of the porcelain facing and rootportion for pontic artificial teeth arranged in such a into which a pinor attaching device is placed manner as to strengthen and give supportto for the purpose of cementing with a dental the labial upright faceagainst lateral and cement to secure the porcelain facing to thedownward pressures. pin attaching device. The pin attach ng de- Afurther ob ect of this lnventlon is to vice is preferably attached to ametal backing provide an upright boxed labial mortise in or cusp plateby means of attaching, known the porcelain to receive an upright labialplate to the metal arts. T he metal backing is made on the metal backinadaptable to the cut away lingual and occlu-v Further objects of thisinvention will ap- 7 sal surfaces of the porcelain root facing and pearfrom the following detailed description upon this metal locking cut awaysurface is of this device and as disclosed in the single provided arecess for adding additional metal sheet of drawings which is herewithmade a to each surface to strengthen the backing for part of thisapplication. stresses as a means for attaching the dummies In thedrawings 0r pontics or abutment pieces together to Fig. 1 represents avertical sectional View form the span portion of metal backing coinof ananterior tooth and root facing showing mon to fixed dental bridgework.the pin or attaching device mounted with Another object of thisinvention is to progold backing and inserted in the tooth; vide apinarrangement or attaching device Fig. 2 illustrates aperspective view ofFl 5 which will slide into the slot or recess of the 1 showing the pinconstruction on the backporcelain facing and root portion and around ingof the attaching device. which is adapted to be, placed dental cementFig. 3 represents a vertical sectional view for securing the porcelainfacing or root to of a tooth and root facing with its pin or atpinattaching device being adapted to be modified form over Fig. 1.

secured to the metal backing common to den- Fig. 4 represents aperspective View of Fig.

tal bridgework. 3, with the pin and backing removed and A. furtherobject of this invention is to showing the slot and tooth surfacearrangefeature which can be done while the bridge Fig. 5 represents avertical sectional view is fastened or placed in the month without of atooth and root facing with pin attaching removing the same from themouth. This is device mounted thereon in slightly modified made possibleby the arrangement of the slot form over Fig. 1. 50 in the porcelainfacingand root portion to- Fig. 6 represents a perspective view of Fi 5with the pin and its backing removed therefrom.

Fig. 7 illustrates a vertical sectional view of a modified form ofanterior tooth and root facing s rowing a pin and backing mountedtherein.

*ig. 8 represents a perspective view of Fig. i with the pin and backingremoved.

F 9 represents a perspective view of the pin and backing adapted to beused in connection with the anterior tooth and root facing disclosed inFigs. 7 and 8.

Numeral 1 designates a porcelain face and rooted tooth adaptedparticularly to the anterior ridge of the month, while numeral 2designates the gold backing having a pin 3 attached thereto by somesuitable means, the backing 2 and pin 3 being integrally joined andadapted to be mounted in place on the porcelain faced tooth 1 in areceiving slot or recess having a specially formed base portion 5adapted to receive a cooperating base section 6 of the pin 3. The baseportions 5 and 6 of the slot and pin may be made to conform to anydesired shape approximately rounded as disclosed in Figs. 1 to 6inclusive or having rectangular shape as disclosed in Fi 7, 8 and 9. Thelingual and occlusal upper portions of the tooth 7 are adapted to be cutaway ano ground to allow the inter changeable gold mounting 2 having theat taching pin 3 with its base portion 6 integrally connected thereto.The pin attaching device 3 and 6 is adapted for insertion into slots 4.-and 5 of the porcelain tooth 1, the attaching pin 8 and 6 being formedpreferably having a flat upright portion with parallel sides, the:forward end of the base portion and of the pin 6 being adapted toextend a short distance ocyond the forward edge of the upright flatportion. of the pin as at 8. The base portion of the slot is so formedas to provide a strong grip, particularly into the greater porcelainbulk at approximately right angles to the occlusal stress on theporcelain. That part of the slot 4 extending upward of the long axis ofthe tooth has approximately parallel walls and a boxed or dovetailedrecess 9 toward the cutting edge of the tooth 10, the upright slotportion 4 in the tooth being adapted to receive the upright pin portion3 on the metal backing 2. By this invention, two surfaces 7 and 11, areformed in the porcelain tooth to receive the two cooperating surfaces 2and 12 of the metal backing, thereby provid ing a two-surface reciprocalanchorage in cooperation with the strengthening qualities of the pin 3and its portions 6, 8 and 9.

One of the most important points in connection with a pontic tooth isthe mechanical and porcelain adaptation. The means of attaching theporcelain pontics must be simple, and give strength where strength ismost desired. It also must lend itself to the widest ran 'e ofapplication. The great problem with the manufacturers of teeth is tofind a tooth that is simple, easy to make, and possessing mechanical andadaptable qualities. Although the various means of attaching these teethmust be similar, yet, the fine variations are very important and are thevery soul of the whole problem. Certainly the adaptability and strengthof body are the points most important. The porcelain form imitates thenatural tooth and conceals as much of the metal backing as possible, foresthetic reasons, principally. The porcelain itself is a kind of veneerand has little strength. It is hard and brittle and must be protectedand supported by a strong metal which will protect it from directcontact with force in chewing, as much as possible. he metal must alsoserve to attach this tooth to the natural teeth in the mouth and to formthe main portion in bridge work.

This invention provides a two surface reciprocal anchorage particularlyadapted for pontics in artificial teeth, and improved means for applyingporcelain 'facings with attached rounded glazed root ends to the gold orother metal backing in dental bridgework, particularly a pin engagingdevice for the purpose of retaining the porcelain facing to the bridgeor backing. The slot in the porcelain facing root is so arranged thatthe base slot portion enters at the lingual side, preferably in thebulky portions of the porcelain and extending about at right angles tothe long axes of the tooth into and at a point close to the labial andbuccal surfaces but not through, thereby providing a. recess slightlybeyond that portion of the slot that receives the upright labial supportflange. The portion of the slot forming the top or occlusal end of themortise is to be formed having a boxed recess in the porcelain body intowhich the labial flange of the metal surface extends to serve asadditional strengthening and supporting means for lateral stressparticularly. Excessive stress on all porcelain facings is lateral andupward, and this invention provides a means for strengthening and tyingthe elements together in such a manner as to relieve the material oflateral and upward strain at the weak point, which is located at thejunction of the cutting edge of the porcelain and metal backing. Thebase of the slot is broader and larger with an extending recess in thelabial and buccal bulk of the porcelain than the upright portion of theslot, this portion may be either round or of any desired shape. The baseportion of the slot is so formed by this invention as to provide astrong grip, particularly into the greater porcelain bulk atapproximately right angles to the occlusal stress on the porcelain whichit is designed to bear. That portion of the slot extending upward withthe long axis of the tooth has approximately parallel walls and a recesstoward the cutting edge of the tooth. The upright slot portion isadapted to receive the upright flange of the metal attachment thusgiving still greater grip to the porcelain when cemented. The uprightmetal flange of the pin serves to function as a brace to the baseportion of the pin and to give reciprocal anchorage for the tooth. It isto be understood that the metal pin attaching device and its mountingmay be modified slightly in order to conform to posterior teeth.

This invention is susceptible to those modifications which would beobvious to Workers in dental and ceramic art without in any waydeparting from the scope and purpose 0 this invention, as for example,to make up the metal pin attachment device mounted permanently to thethin metal backing to conform to the cut away and occlusal surfaces ofthe porcelain or without this backing but with the pin extendingslightly out of the slot to allow an inset of the pin for the backing inany way suitable to the art. Obviously, the pinattaching device is madeof a suitable metal and is formed to fit into the slot arranged in theporcelain portion allowing room for interposing the dental cement forsecuring purposes.

This invention provides a two-surface reciprocal anchorage forartificial teeth comprising a porcelain facing having a root or baseextension somewhat rounded or egg shape with or without the ridgelingual portion sliced ofi to allow the root end to saddle over orconform to the dental ridge, the porcelain facing or base having a roundor rectangular bore in its lingual base extending forwardly, a boxedlike slot extending into the face of the porcelain, the slot beingthinner than the base bore, the lateral walls of the slot beingapproximately parallel the labial incisal portion of the slot being aboxed like undercut having its top plane corresponding to the directionof the base bore as disclosed particularly in Fig. 7 the base and slotentering on the lingual side and extending forwardly in the face andbulky portion of the porcelain approximately at a right angle to theface of the tooth, or as disclosed in Fig. 1 cylindrically from the rootlingual side upwardly toward the face incisal side at an angle of about120 degrees d1- verging to the face of the tooth. The pin and labialfiange tongue of the backing being formed to be received into the boreand slot, the backing to conform to the two lingual surface planes ofthe percelain.

This invention provides an artificial porcelain faced tooth having arounded root end adapted for dummies and pontics in dental bridgeworkand is reciprocal or interchangeable in case of fracture and breakage orfor the purpose of grinding, fitting, adding to glazing or changingcolor while the bridgeis either in or out of the mouth.

What I claim is:

In an artificial tooth, an anchorage comprising a, facing having a rootextension, two surfaces on the lingual side, a metal backing to fitthereon, a base surface extending from the lingual side approximately atright angles to the long axis of the tooth toward the labial and buccalsurfaces and adapted to merge with a second surface extending from theincisal edge toward the root end thereby forming an angle having twosurfaces at approximately right angles to each other, the base surfaceand second surface having a slot therein adapted to receive a tongueportion f of the backing.

In testimony whereof I aflix my signature.

BENJAMIN L. BROOKS.

